资料e-mobility manual

1、E-Mobility ManualVersion 1.01ContentIntroduction Electric Vehicles3Efficiency Analysis4Electrification of Drivetrain6Measurement Configuration7Voltage Measurement9Current Measurement11Additional Data Acquisition13DEWESoft Setup14Analog setup and storing options14Power module for AC P

2、ower Analysis15Math for DC Power16Efficiency17Analysis Capabilities of DEWESoft18Example: Efficiency Flow of Electric Car19Further Exemplary Results21Charging Process22Battery Testing24Hybrid Car Testing25Hydrogen Car Testing25Pictures of Analysis Ford Focus Electric Real-Drive Test26Pictures of Ana

3、lysis Electric Two-Wheeler28Pictures of Analysis 7-Phase AC In-Wheel Motors29Pictures of Analysis Test-bench & Climate Test-Chamber31Pictures of Analysis Electric & Hybrid Vehicle TIntroduction Electric VehiclesAs the transportation sector is a major polluter with high le

4、vels of greenhouse gas emissions,steps must be taken to reduce the emission rates. While conventional vehicles (Gasoline, Diesel) produce different kind of emissions at the combustion process (CO2, NOx, SO2, HCs, CO, NH3, fine dust, etc.) electric vehicles dont produce emissions during operation.Ano

5、ther main advantage of electric vehicles is the high efficiency of the electric motor. The electric motor has a much higher efficiency than a conventional internal combustion engine. A further advantage is the possibility of high-efficient energy recuperation during brake process, downhill driving,

6、etc.ummary electric vehicles are very efficient and doesnt produce emissions during operation. The real efficiency and emissions only depends on the way the electricity is produced.To achieve a significant reduction of emissions, a change from the use of fossil fuels to low or zero emission energy s

7、ources is required. Electric vehicles will play a leading role in achieving sustainable and energy-efficient mobility.Nowadays the determination of energy consumption and CO2 emissions is done at testbenches by means of standardised driving cycles (NEFZ, WMTC etc.). For determining the energy consum

8、ption of electric vehicles this way doesnt fit due to several reasons: no consideration of recuperation, no consideration of auxiliary loads, tests are done at ideal testing conditions, etc. All-in-all the real energy consumption of vehicles can be up to 60% higher2.Therefore comprehensive efficienc

9、y analysis of electric vehicles on test-bed and also duringreal-driving conditions is necessary to get reliable results. This requires a powerfulmeasurementtrument. Analysis during real-driving operation additionally requires a verycompact and battery-powered measurement system which is able to supp

10、ly all sensors directlyout of the measurementtrument. DEWESoft offers with the DEWESoft Power Analyserproduct line the ideal solution for measurement applications like Efficiency Analysis2The real energy consumption of (electric) vehicles can deviate up to 60 % of themanufactur

11、ers specifications. To understand how such deviations can occur, we first analysedthe factors which have the highest influence on the energy consumption. The following table shows how much the individual factors can influence the energy consumption.Table 1: Factors which influence energy consumption

12、 of electric vehicles mainlyAs you can see there are a lot of factors which can influence the energy consumptionsubstantially. As reference for this comparison, the averaged energy consumption of the tested electric vehicle was used.If the manufacturer specification is done at ideal conditions (idea

13、l ambient temperature, noauxiliary loads, no uphill etc.) the energy consumption is a lot lower than in reality. Therefore it is important to consider everything if you want to get reproducible and realistic specifications for energy consumption.Notably weather conditions can have a high impact. For

14、 example the difference of doingefficiency analysis at very cold weather (-40C) compared to ambient temperatures of about 20C can influence the energy consumption of up to 100%. This means that the range of the electric vehicle is halved at this temperature. Also hot weather (e.g. +30C) influences t

15、he energy consumption significantly as cooling is necessary. This can lead to about 15% more energy consumption.Different test drivers, auxiliary loads, the route (city, overland) can influence the energyconsumption of up to 10% (each of them). The energy consumption is especially high when driving

16、uphill: up to 8 times higher than the averaged energy consumption.This results explahow deviations of up to 60% of the manufacturers specification can occur.If the manufacturer specification is done at ideal conditions (ideal ambient temperature, noauxiliary loads, no uphill etc.) the energy consump

17、tion is a lot lower than in reality. Therefore DescriptionEnergy ConsumptionReference Energy consumption 20 kWh/100km 4 Driving cycle on testbench 60 % 2Temperature-depended capacity of HEV-battery 10 % 4Behaviour of test driver (aggressive driving) 10 % 1Drive train technology (H

18、ybrid Vehicles)+ 20 % 4Hot weather (Cooling)+ 20 %Cold weather (Heating)+ 100 %Uphill+ 800 % 1Auxiliary loads (e.g. light, fans, radio etc.) 10 %Speed 130 km/h+ 100 %Charging Efficiency+ 200 %is important to consider everything if you want to get reproducible and realistic specificationsfor energy c

19、onsumption.For efficiency optimisation its also important to see the relationship between the differentfactors which influence the energy consumption. The following screenshot shows the interconnection between the different factors which influence energy consumption:TyrediaSpeedSurRangeThis shows im

20、pressive the relationship & dependence between the different factors. Forexample using a bigger & heavier battery pack influences vehicle mass and therefor acceleration force, roll resistance etc. So the car needs more power & energy. Vice versa bigger battery packs have higher capacity and more ran

21、DowntSlopePosition DriverRoadprofil &PowerEnergyBattery Size meterfaceDriver BehaviourVehicle Masshrust forceTorqueVehicleConstructionAcceleration ForceAir ResistanceRoll resistanceBattery TechnologyElectrification of DrivetrainThe electrification of vehicle drivetracan be realis

22、ed in a couple of different ways (one tofour motors, motor & generator, in-wheel motors, fuel cell, 1 to 12 phase motors etc.). Thesimplest configuration is having one electric motor which is controlled by an inverter and powered by a battery, see:In this case we would at least need four voltage and

23、 four current channels to determine theefficiency and energy consumption of the vehicle.But there are also a couple of other possibilities how of how the drive-train for an electriccar can realised. See in the following picture electric drivetraseries and parallel hybrid car and a hydrogen car.with

24、four in-wheel motors, aFigure 1 - Parallel hybrid vehicle 3Figure 2 - Vehicle with 4x In-wheel motors3Figure 3 - Vehicle with Fuel cell3Figure 4 - Series hybrid vehicle3In this cases already a lot more voltage and current input channels and also others (e.g.Combustion Analysis etc.) would be needed.

25、This shows that testing of this vehicles needs a really flexible and powerful measurement system. The DEWESoft Power Analyser makes it possible to do analysis for all kind of drivetra (Electric, Hybrid, Hydrogen) and as well for all applications (test-bench, real-driving).6Measuremen

26、t ConfigurationTo analyse all necessary data online during measurement there are several requirements onthe measurement system. The measurement system must be able to measure the power atdifferent pointside the vehicle completely synchronous. Using conventional measurementequipment would require the

27、 use of a several power analysers, data loggers, GPS loggers etc.Challenges like data merging, data synchronisation, power supply of the truments (independent of the vehicle battery), etc. make it nearly impossible to get reliable measurement results in this way.To tackle all these problems in a con

28、venient way, we choose the DEWESoft R8D Power Analyser, which allows to measure up to 8 three phase systems at the same time. The DEWESoft Power Analyser combines all the functionality of a power analyser, an oscilloscope, a data logger, an FFT spectrum analyser and a transient recorder. In combinat

29、ion with the powerful hardware and the high number of input channels, comprehensive analysis of the whole vehicle power train and power system are possible. The system also has a built in battery pack which allows supplying the measurement device and all sensors (current clamps, GPS, video, etc.)dir

30、ectly out of thetrument itself. This ensures reliable and authentic results for efficiencyanalysis under real driving conditions. In addition to the voltage and current measurement alsoa GPS sensor and a video camera were connected to the system for detailed analysis (energy consumption for downhill

31、, uphill, city, etc.).The following chart shows a schematic of the measurement configuration of an electric vehiclewhich is powered by one electric motor:7The following chart shows a schematic of the measurement configuration of an electric vehiclewhich is realised with motor and gen

32、erator and also auxiliary loads on DC side were measured.AC & DCDEWESoft R8D PowerFigure 5: Measurement configuration using the DEWESoft R8D Power AnalyserAs the motors of electric vehicles are controlled by inverters with high switching frequenciesit is necessary to do the data acquisition for volt

33、age and current with high sampling rate. The high accuracy (0.05 %), high sampling rate (up to 1 MS/s) and high bandwidth (2 MHz) of DEWESoft Sirius high-voltage and low-voltage input amplifiers ensures highest accurate analysis for a wide variety of applications (inverter, motor, battery, charging

34、processes, efficiency, and a lot more).The DEWESoft Power Analysis software module allows measuring every kind of motor (1 to 12phase AC) and inverter (DC-AC, AC-AC, switching frequencies up to some 100 kHz) at multiple points completely synchronous. This unique feature allows comprehensive analysis

35、 for all typesof electric drivetra(single motor, motor and generator, 2-4x in-wheel-motors) and theconsideration of other loads (heating, air-conditioning, 24V, 12V, etc.). It is also possible tomeasure wireless in-wheel motors due to the high-sampling rate and bandwidth of the DEWESoft Power Analys

36、er. Due to the compact size of the DEWESoft SIRIUS PWR Power Analyser it is even possible to measure the efficiency of electric motorcycles and electric two- wheelers under real-driving conditions. The system can be used either on the test-bed or on the test Voltage Measuremen

37、tA main challenge at measuring at electric vehicles is the voltage measurement. One challengeis to get access to battery or motor voltages, as they are really good protected due to safety reasons. Sometimes its even necessary to open the power inverter (powertrain cradle) to get access to the batter

38、y and phase voltages. Another challenge are the high-voltage level and safety reasons. The battery voltage of an electric vehicle can be up to more than 1000Volts.The DEWESoft Sirius HS-HV amplifiers are the perfect fit for such application as they have an high-measurement range of up to 1600V DC an

39、d, as they are fully isolated amplifiers, also have high isolation voltage of 2 kV In-to-GND (4kVp In-to-In). The following table shows the specs of the high-voltage inputs.Battery VoltageThe measurement of battery voltage (DC) can be done directly. The Plus and Minus line are connected to In+ respe

40、ctive In-.Motor Voltages:As the voltage of the inverter is a PWM modulated signal with a high-switching frequency necessarily voltage inputs with high-bandwidth and high-sampling rate are needed. The following picture shows the frequency spectrum of the different parts of the signal.Switching freque

41、ncies of vehicle inverters can be up to 100 kHz. If Wireless Power transfer isused (e.g. wireless charging, wireless in-wheelmotor) switching frequencies can be even higher.For accurate Power Analysis and also detailed inverter analysis (dU/dt) high bandwidth and high-sampling rate are very importan

42、Motor Voltages Delta ConfigurationIf motor voltages are connected via Deltaconfiguration the voltages can be connected directly, like in the following picture:Motor Voltages Star ConfigurationIf motor voltages are connected via Star configuration mosttime its necessary to use a St

43、arpointadapter. Only if the starpoint of the motor is accessible a Starpointadapter is not necessary. Otherwise a starpointadapter is necessary to adjust impedance of the high-voltage inputs to the impedance of motor-inverter line.If there is no starpointadapter connected the voltages will floatlike

44、 you see in the following picture:By using the DEWESoft starpointadapter the voltages are now stable, see picture:10Current MeasurementThe current measurement of battery and motor can be very challenging as well. Most time there are used zero-flux transducers or current clamps. The L

45、ow-Voltage input module of DEWESoft allows to connect any sensor (Shunt, Clamps, Rogowsky Coils, Zero-Flux transducers) to the system. All DEWESoft current transducers will be automatically detected by the software (TEDS) and also automatically supplied with power. For E-Mobility application only th

46、e AC/DC clamps (DS-CLAMP-150DC, DS-CLAMP-200DC, DS-CLAMP-500DC and DS-CLAMP-1800DC) andthe zeroflux transducers (IT-S X00) are used as iron-core clamps and rogowsky coils are not capable of measuring DC. Rogowsky Coils are only used exceptional for motor current analysis whenever there is no space t

47、o use clamps or zero-flux transducers and its also not possible to use a shunt.The following table shows a comparison between the different type of current transducers concerning accuracy, bandwidth, measurement range etc.To proof this determination we tested different current sensors at the motor l

48、ine see pictureof measurement configuration:11PropertiesApplicationTypeACDCRangeAccuracyBandwidthProsConsPower AnalyserE-MobilityGrid MonitoringIron-Core ClampYesNo5 kA0,5 - 4 %10 kHzCheap- Heavy- not flexible- no DC- low bandwidthNoNoYesCheap Rogowsky CoilYesNo10 kA1%20 kHz- rugged,

49、 flexible- Linear- No magnetic influence- Overload withstand capability- No DC- Positioning ErrorNoNoYesGood Rogowsky CoilYesNo50 kA0,30%up to 20 MHz- rugged, flexible- Linear- No magnetic influence- Overload withstand capability- No DC- Positioning ErrorpartlypartlyYesHall compensated AC/DC ClampYe

50、sYes300 A0,50%100 kHz- AC & DC- high accuracy- high bandwidth- it can be opened- low measurement rangeYesYesYesZero-Flux TransducersYesYes1000 Ahighest accuracyup to 300 kHz- AC & DC- highest accuracy- highbandwidth- low phase error- low offset- not to openYesYesYesSee the results in the following t

51、able:Shielded Motor CableAn often asked question is the influence if its measured with or without shielded motor cable.Also for this we did some investigation, see in the following picture the measurement configuration.The answer is YES there is a difference, but the effects strongly depend on the t

52、ype of electricvehicle and the realisation of the drivetrain. At the car we did this analysis the following behaviour was worked out.The current signal of the shielded motor cable was smoothed compared to the currentsignal without shield.The current signal of the shielded motor cable was damped at h

53、igher frequencies There was a frequency-depended phase shift between the signals (up to 15).The signal of shielded motor cable has a higher DC partAll-in-all the signal at measuring with shielded motor cable therefore has Low-Pass Characteristics. 12DS-CLAMP- 200ACDS-FLEX-300DS-CLAMP

54、- 150DCIT-S 600TechnologyIron-coreRogowskyHall-effectZero-fluxDCNot possibleNot possibleHigh accuracyHighest accuracyAC up to 15 HzDistorted waveformOscillationsHigh accuracyHighest accuracyAC 15 Hz and 400 HzModerate accuracyHigh accuracyHigh accuracyHighest accuracyHigher Frequency componentsBandw

55、idth limited to 10 kHzHigh accuracy - (bandwidth depends on integrator)High accuracy up to 100 kHzHigh accuracy up to 500 kHzAdditional Data AcquisitionBeside the analysis of electrical parameters its also possible to measure any other signals likeanaloge, digital, counter, GPS, Video, Data from Interfaces DEWESoft SetupAnalog setup and storing optionsAs the motors of electric vehicles are controlled by inverters with high switching frequencies it is necessary to do the data acquisition for voltage and current with high sampling rate. So thef